[Armadillo:07301] Re: Armadillo-420のCON9にオーディオ機能を割り当てたい

[Takenoshita Koyo]

> /usr/share/alsa/cards/aliases.conf　が無いと言っているので
/etc/asound.confが、/usr/share/alsa/cards/aliases.conf の代わりをしてくれます。

あるコマンドを実行したときに、どのファイルが使用されているのかは、
straceを使って調べることができます。

/etc/asound.confが*ある*場合は、以下のように/usr/share/alsa/alsa.confを見にいき、
その後、/etc/asound.confを見にいきます。
[armadillo ~]# strace aplay -M /dev/urandom 2>&1 | grep open
open("/etc/ld.so.cache", O_RDONLY)      = -1 ENOENT (No such file or directory)
open("/lib/tls/v5l/fast-mult/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/lib/tls/v5l/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/lib/tls/fast-mult/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/lib/tls/libc.so.6", O_RDONLY)    = -1 ENOENT (No such file or directory)
open("/lib/v5l/fast-mult/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/lib/v5l/libc.so.6", O_RDONLY)    = -1 ENOENT (No such file or directory)
open("/lib/fast-mult/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/lib/libc.so.6", O_RDONLY)        = 3
open("/lib/libasound.so.2", O_RDONLY)   = 3
open("/lib/libgcc_s.so.1", O_RDONLY)    = 3
open("/lib/libm.so.6", O_RDONLY)        = 3
open("/lib/libdl.so.2", O_RDONLY)       = 3
open("/lib/libpthread.so.0", O_RDONLY)  = 3
open("/lib/librt.so.1", O_RDONLY)       = 3
open("/usr/share/alsa/alsa.conf", O_RDONLY) = 3
open("/etc/asound.conf", O_RDONLY)      = 3
open("/dev/snd/controlC0", O_RDWR)      = 3
open("/dev/snd/pcmC0D0p", O_RDWR|O_NONBLOCK) = 4
open("/dev/urandom", O_RDONLY|O_LARGEFILE) = 3

/etc/asound.confが*ない*場合は、以下のように/usr/share/alsa/alsa.confを見にいき、
その後、/usr/share/alsa/cards/aliases.confを見にいきますが、ファイルが無いので
エラーになっています。
[armadillo ~]# ./strace aplay -M /dev/urandom 2>&1 | grep open
open("/etc/ld.so.cache", O_RDONLY)      = -1 ENOENT (No such file or directory)
open("/lib/tls/v5l/fast-mult/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/lib/tls/v5l/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/lib/tls/fast-mult/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/lib/tls/libc.so.6", O_RDONLY)    = -1 ENOENT (No such file or directory)
open("/lib/v5l/fast-mult/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/lib/v5l/libc.so.6", O_RDONLY)    = -1 ENOENT (No such file or directory)
open("/lib/fast-mult/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/lib/libc.so.6", O_RDONLY)        = 3
open("/lib/libasound.so.2", O_RDONLY)   = 3
open("/lib/libgcc_s.so.1", O_RDONLY)    = 3
open("/lib/libm.so.6", O_RDONLY)        = 3
open("/lib/libdl.so.2", O_RDONLY)       = 3
open("/lib/libpthread.so.0", O_RDONLY)  = 3
open("/lib/librt.so.1", O_RDONLY)       = 3
open("/usr/share/alsa/alsa.conf", O_RDONLY) = 3
open("/usr/share/alsa/cards/aliases.conf", O_RDONLY) = -1 ENOENT (No such file or directory)
(後略)

ということで、
> /usr/share/alsa/cards/aliases.conf　が無いと言っているので
というエラーが出ているからといって、必ずしも/usr/share/alsa/cards/aliases.conf
を用意しないといけないというわけではありません。

-- 
Koyo Takenoshita